Today we celebrate the birthday of Martin Gardner. Gardner, born in 1914, was a science writer specialising in the field of recreational mathematics, but also covering topics like magic, literature, scientific scepticism, philosophy and religion.

His most famous contribution to the popularisation of science and mathematics was the ‘Mathematical Games’ column he wrote for Scientific American for 25 year, between 1956 and 1981. Many of these columns have been collected and published as a series of books starting with ‘Mathematical Puzzles and Diversions’, first published in 1956.

So popular was Gardner (who passed away recently in 2010) that, in honour of his life and work, his birth date of October 21 has come to be known as the ‘Celebration of the Mind’. The Gathering for Gardner Foundation aims to use this day to “celebrate Martin’s life and work, and continue his pursuit of a playful and fun approach to Mathematics, Science, Art, Magic, Puzzles and all of his other interests and writings.” They encourage people to get together on the day to share mathematical or logic puzzles, paradoxes, illusions and magic tricks, or just in general engage in activities that gets the logical side of your brain buzzing.

One of the classic Gardner puzzles. Rearrange a triangle made up of six coins into a hexagon, by moving one coin at a time, with each move leaving every coin touching at least two others, as seen in the pictures.

Examples of Gardner’s puzzles are readily available online. To immerse yourself in his world of puzzles, start with the classics on puzzles.com. There’s also an edition of the College Mathematics Journal dedicated to Martin Gardner available for free from the Mathematical Association of America.

As a teaser, here’s a few from the Gathering for Gardner website:

• A woman either always answers truthfully, always answers falsely, or alternates true and false answers.  How, in two questions, each answered by yes or no, can you determine whether she is a truther, a liar, or an alternater?
• You are in a room with no metal objects except for two iron rods. Only one of them is a magnet. How can you identify which one is a magnet?
• Mr. Smith has two children.  At least one of them is a boy.  What is the probability that both children are boys?  Mr. Jones has two children.  The older child is a girl.  What is the probability that both children are girls?

Besides his interest in recreational mathematics, Gardner was an outspoken scientific sceptic with an uncompromising attitude towards pseudoscience. In his books he commented critically on a range of ‘fringe sciences’, from creationism to scientology to UFOs and the paranormal. This earned him many fans, but also many antagonists, particularly individuals operating in these fringe domains. While critical of conservative Christianity, Gardner considered himself a ‘fideistic deist’, believing in a god as creator, but critical of organized religion.

Gardner was also a leading authority on Lewis Carroll. He published ‘The Annotated Alice’, an annotated version of ‘Alice’s Adventures in Wonderland’ and ‘Through the Looking Glass’, where he discussed and explained the riddles, wordplay and literary references found in Carroll’s works. He also produced similar annotations of GK Chesterton’s works, ‘The Innocence Of Father Brown’ and ‘The Man Who Was Thursday’

Yet his most enduring contribution remains in the field of recreational mathematics and puzzles. It has famously been said that, through his writings on puzzles, tricks and paradoxes, he “turned thousands of children into mathematicians, and thousands of mathematicians into children”.